Draft regulator



Jan. 14, 1941. W B, STEPHENSON 2,228,857

DRAFT REGULATOR Filed March 9, 1938 Patented Jan. 14, 1941 UNITED. STATES f j Y '2,228,857

PATENT OFFICE DRAFT REGULATOR William B. Stephenson, Fond du Lac, Wis.

Application March 9,.

4 Claims.

The present invention relates to improvements in draft regulators, and has particular reference to a new and improved regulator with an adjustable mounting adaptable to flue passages of different sizes.

The invention is especially applicable to automatic draft controllers for regulating the admission of atmospheric air into the flue gas outlet passage of the heating apparatus so as to mainmined desired intensity in the fire box regardless of fluctuations in the conditions tending to induce the draft. One type of such automatic draft controller is disclosed in Patent No. 2004,947 issued to Irsch and Stephenson.

An automatic regulator of this type is commonly mounted in the outer end of a stub pipe defining a branch air inlet passage, and connected at the other end to a pipe or breeching defining the main flue gas outlet passage of the heating apparatus. Flue pipes are provided in different diametrical sizes, and it has, therefore, been necessary heretofore to provide stub pipes and draft regulators in a corresponding range of sizes. One of the primary objects of the present invention is to provide a draft regulator having a novel supporting pipe or housing which is readily adjustable for suitable connection to flue pipes or breechings of different sizes, and which in any condition of adjustment will support a regulating damper or valve of one predetermined size, thereby reducing the number of duplicate parts of assorted sizes that would otherwise be kept in stock.

Another object is to provide a new and improved draft regulator of the foregoing character in which the damper is adjustably mounted with a tight and secure fit on the supporting pipe in all adjustments of the latter for iiue pipes of different sizes.

A general object is to provide a novel draft regulator of the foregoing character which is simple and inexpensive in construction, and which is adapted to be easily and quickly installed.

Further objects and advantages will become apparent as the description proceeds.

In the accompanying drawing,

Figure lis a perspective view of a draft regulator embodying the features of my invention.

Fig. 2 is a side elevational view of the regulator.

Fig. 3 is a top view of the regulator, one adjustment being shown in full outline, and antain in normal operation a draft of a predeter- 193s, serial' No. 194,722

other adjustment being indicated in dotted out-- line. Y

Fig. 4 is an end elevational view.

Figs` 5, 6 land 7 are fragmentary detail sectional views, on an enlarged scale, taken re- 5 spectively along lines 4-4, 5-5 and 6--6 of Figs.

2 and 3.

While the invention is susceptible of various modifications and alternative constructions, I have shown in the drawing and will herein de- 10 scribe in detail the preferred embodiment, but it is to be understood that I do not thereby intend to limit the invention to the specific form disclosed, but intend to cover all modifications and alternative constructions falling within the 15 spirit and scope of the invention as expressed in the appended claims.

Referring more particularly to the drawing, the draft regulator, constituting the exemplary embodiment of the invention, is adapted to be 20 mounted on a suitable breeching, such as a cylindrical pipe or duct l, open to or defining a flue gas outlet passage from the heating apparatus (not sho-wn). The draft regulator comprises a housing, such as a stub pipe or duct 8, one end 25 of which is interfitted with and suitably connected to theduct 1, and which defines a branch atmospheric air inlet passage. The duct 8 is generally cylindrical, and has diametrically spaced end extensions 9 secured, as by means 3.0 of screws I0, to opposite sides of the .duct 1. The side edges `of the extensions 9 are curved to conform substantially to the curvature of the duct 'l. The foregoing manner of attachment is simple, and can be easily and quickly accom- 3'5l plished.

Mounted in association with the outer end of the duct or sleeve 8 is a damper or valve Il for controlling the flow of air therethrough. Within the broad concept of the invention, the damper 40" H may be of any suitable type and form. In the present instance, the damper Il consists of a fiat circular plate supported for swinging movement., on pintles I2 defining a transverse axis, in a mounting ring I3 suitably secured in the outer 45- end of the duct 8, The damper plate H may be of the automatic type, tending to move toward and into closed position in response to the action of countervveight means Ila adjustably mounted thereon, and adapted to open in response to the 505 ing apparatus. 55

To provide suitable means for securing the damper plate II in operative position, the outer end of the duct 8 adjacent the circular edge is formed with an internal peripheral bead or rib I4 which interfits with an external groove I5 in the damper rim or mounting ring I3. The bead I4 and groove I5 have a tight sliding t permitting rotary adjustment of the damper plate II about the longitudinal axis of the duct 8.

One of the features of the present invention resides in the adjustability of the duct 8 whereby the dlraft regulator of a given size can be adapted for usev with flue pipes or ducts 1 of dilerent sizes. In the preferred form, the duct 8 consists of two opposed substantially semicylindrical sections I6 and I'I which have overlapping longitudinal edge por-tions, and which are pivotally connected at their outer ends for relative angular adjustment about an axis extending diametrically of the bead I4 and in a plane transversely between the opposite vend extensions 9. The pivotal connection is eected by means of suitable flat-headedl bolts I8 extending outwardly through registering apertures I9 formed in the overlapping marginal portions o-f the duct sections I6 and I'I in the plane of the bead I4, To avoid interference with the damper mounting ring I3, the bead I4 is interrupted in the region of the apertures I9, and the metal about the latter is stamped outwardly to accommodate the heads of the bolts I8.

At the other end, the marginal longitudinal edge portions of lthe sections l5 andi Il are adapted to be secured in different degrees of overlap so as to adjust the diametrical size of the duct 8 for flue ducts 1 of different sizes. The means for this purpose, at each side of the yduct 8, consists of one aperture 28 in one of the sections and movable selectively into registration with any one of a plurality of apertures 2l, for example, two, in the other section, and a bolt 22 extending through the registering apertures. So that both sections I6 and I 'I may be of the same construction, each is formed with an aperture 28 in one marginal edge portion, and with apertures 2| in the other marginal edge portion. Preferably, the marginal edge portions with the apertures 2i are disposed on the inside against the marginal edge portions with the single apertures 20.

t will be evident that the attachment end of lthe duct 8 may be expanded or contracted by selective adjustment of standard parts to fit flue ducts 'I of diferent sizes, and that this adjustment may be simply and quickly effected. However,

.the outer end of the yduct 8 remains the saine in size since the pivotal axis of the sections I6 and II is in the plane of the bead I4, and hence draft regulating dampers II of one standard size may be used for diiferent adjustments. The range of adjustment necessary to satisfy practical requirements in a duct 8 of ordinary length is not sufciently large to displace the sections of the bead I4 materially or objectionably out of a common plane, nor to deviate from a substantiallyvcircular form at the attachment end of the duct. Moreover, after the desired adjustment for size, the extensions 9 may be slightly flexed relatively to each other to vary the curvature of the side edges and to correct the form of theduct 8 if it appears desirable, the initial adjustment being such as to compensate for the flexure.

With the foregoing construction, ducts 8 and dampers II, of assorted sizes, need not be kept in stock for flue ducts I of diierent sizes within a reasonable range. One adjustable duct 8 and one damper I I of standard size will serve for ducts 1 of a variety of sizes.

Within the broad aspects of the invention, the sections I 6 ancl I1 may be provided in any suitable shape, They are herein disclosed as being substantially semicylindrical in form so that when assembled they denne a duct 8 substantially circular in lateral cross section. However, the sections could be so formed that the duct 8 would be substantially square or rectangular in lateral cross section.

I claim as my invention:

1. Draft control supporting means comprising, in combination, an air inlet duct having two diametrically opposite longitudinal sections with closely overlapping longitudinal marginal edge portions,` the overlapping marginal edge portions of said sections being pivotally connected at the outer end of said dluct for relative angular adjustment of said sections about a transverse axis, means for releasably connecting the longitudinal marginal edge portions at the other end of said duct in different selective positions of adjustment of said sections, and means for supporting a draft control in the outer end of said duct in the plane of said axis.

2. A draft control comprising, in combinati-on, a duct having two generally semicylindrical opposed sleeve sections with longitudinal marginal edge portions in closely overlapping relation to dene a by-pass air inlet passage, pivot means connecting the outer ends of said sections at the overlapping marginal edge portions for relative angular adjustment of said sections about a diametrical axis, intermediate longitudinal extensions on said sections at the other end of said duct and adapted to embrace and to be secured to 0pposite sides of a flue duct and having side edges formed to conform to the shape of said flue duct, releasable means for securing the overlapping marginal edge portions together at the other end of said duct in ydifferent selective positions of adjustment to vary the lateral spacing of said extensions for flue ducts of dierent sizes, an automatic draft control having a circular frame mounted in the outer end of said duct and having an external peripheral groove in the transverse plane of said axis, and an internal peripheral rib in the outer end of said duct and engaging in said groove to hold said control in position.

3. In a draft control, a duct having a plurality of peripheral sections pivotally connected at one end to dene an inlet opening of constant area adapted to be controlled by a draft regulator, and means for connecting said sections in dilferent positions of relative pivotal adjustment to vary the size of the other end of said duct.

4. A supporting structure for operatively associating a draft control with a flue passage having, in combination, an air duct having an outer portion of fixedv transverse size to receive a draft regulator of predetermined dimensions and including a plurality of coacting sections relatively adjustable to define a `duct end of variable dimensions for connection with flue passages of diiferent sizes.

WILLIAM B. STEPHENSON. 

